Crankcase ventilation device for vehicle

Abstract

The present invention relates to a crankcase ventilation device for a vehicle and, more specifically, to a crankcase ventilation device for a vehicle, which: prevents a back flow of blow-by gas to a new air inflow valve according to a rise in pressure and a rise in a flow rate inside a crankcase; prevents deterioration in the inside of an engine due to unburned fuel contained in the blow-by gas and minute particles of engine oil, generation of sludge, and an engine failure; and minimizes contamination of an intake system by providing a new air inflow control valve having a nozzle and a diaphragm, so as to block a back flow of the blow-by gas to a new air inflow hose due to an excessive rise in pressure inside the crankcase during a process for re-circulating and re-burning the blow-by gas discharged from the crankcase of the vehicle.

The invention claimed is: 
     
       1. A crankcase ventilation device for a vehicle comprising:
 a crankcase ( 400 ); and 
 a cam cover ( 300 ) situated on the upper side of the crank case ( 400 ) to seal the crankcase ( 400 ); 
 wherein the cam cover ( 300 ) comprises: 
 a fresh air inflow control valve ( 310 ) situated on the cam cover ( 300 ), one side of which is connected to the cam cover ( 300 ) and an opposite side of which is connected to a fresh air inflow hose ( 220 ) so that fresh air is introduced into the crank case ( 400 ); and 
 a pressure control valve ( 320 ) situated on the upper side of the cam cover ( 300 ) to control a pressure in the crankcase ( 400 ); 
 wherein a nozzle ( 311 ) is situated in the interior of the fresh air inflow hose ( 220 ) of the fresh air inflow control valve ( 310 ), and the nozzle ( 311 ) controls inflows of the fresh air into the crankcase ( 400 ) according to a control of the pressure in the crankcase ( 400 ) of the pressure control valve ( 320 ); 
 wherein a diaphragm ( 312 ) is situated on the lower side of the nozzle ( 311 ) to prevent backward flows of a blow-by gas to the fresh air inflow hose ( 220 ). 
 
     
     
       2. The crankcase ventilation device according to  claim 1 , further comprising:
 an oil separator ( 330 ) communicated with the pressure control valve ( 320 ) to separate oil particles from the blow-by gas discharged from the crank case ( 400 ). 
 
     
     
       3. The crankcase ventilation device according to  claim 2 , wherein the pressure control valve ( 320 ) is any one of an orifice valve, a pressure reducing valve, and a solenoid valve electrically connected to an ECU. 
     
     
       4. The crankcase ventilation device according to  claim 1 , wherein in a low-speed/middle-speed of an engine provided with the crankcase ventilation device for a vehicle, the pressure control valve ( 320 ) is opened according to the amount of generated blow-by gas in the crankcase ( 400 ) such that the blow-by gas in the crankcase ( 400 ) flows into an intake manifold ( 500 ) and is mixed with the fresh air supplied from the air inflow hose ( 210 ) to be reintroduced into the crankcase ( 400 ) and burned again, and the fresh air is introduced into the crankcase ( 400 ) through the fresh air inflow control valve ( 310 ). 
     
     
       5. The crankcase ventilation device according to  claim 1 , wherein in a high-speed condition of an engine provided with the crankcase ventilation device for a vehicle, the amount of the blow-by gas in the crankcase ( 400 ) increases so that when the blow-by gas is introduced into the fresh air inflow hose ( 220 ), the blow-by gas is prevented from being introduced into the fresh air inflow hose ( 220 ) through the fresh air inflow control valve ( 310 ).